The Islamic State of Iraq and Syria (ISIS) fashions itself as a band of holy warriors creating an Islamic caliphate carved out of the two nations in its name. Nobody else has to buy into that lie — but it's still important that we don't feed it. Religion confers a patina of legitimacy and even righteousness on those who march under its various banners. And there's nothing holy about ISIS.

Don't take my word for it. Pope Francis' unofficial benediction of an international effort "to stop the unjust aggressor," ISIS, got a lot of attention last week. The day after the pope shared his thoughts on the subject, though, Grand Mufti Sheikh Abdul Aziz al-Sheikh, the top cleric in Saudi Arabia, called ISIS "enemy No. 1 of Islam." His statement, released by the official Saudi Press Agency, also compared ISIS to a heretical sect of Islam called the Kharijite movement. But the grand mufti's key sentence is worth reading in whole:

Extremist and militant ideas and terrorism which spread decay on Earth, destroying human civilization, are not in any way part of Islam, but are enemy No. 1 of Islam, and Muslims are their first victims. [Aziz al-Sheikh]

Now, there's a little bit of hypocrisy here, because senior clerics in Saudi Arabia's ultraconservative Wahhabi sect of Sunni Islam, as Reuters points out, also "endorse execution by beheading for offenses that include apostasy, adultery, and sorcery" — so long as said beheadings are not carried out by rebels. But it's still a significant slap at ISIS and its leader, Abu Bakr al-Baghdadi — who now calls himself Caliph Ibrahim — from a leading religious fellow Sunni.

The religious geopolitics of the Middle East are complicated, but everyone in the region seems to despise ISIS — even al Qaeda, which kicked the group out of its organization. With the brutal public murder of journalist James Foley, the U.S. has some skin in the game. But the local hatred of ISIS is the main story. It's just not the story Baghdadi wants to tell.

Christopher Dickey at The Daily Beast is convinced that the statement by Pope Francis, as well as other high-ranking Catholic and Anglican prelates whose words seem to support the U.S. bomb strikes, are playing into Baghdadi's attempts to "provoke a 21st-century crusade against his Islamic State." Dickey continues:

He wants to force his enemies into a religious war arousing atavistic instincts rooted in the Middle Ages — the great glory days of Islam — that linger in the hearts of many Muslims around the world. And by every indication he is succeeding. With each American bomb that falls and each drone that flies over the territories the caliph has conquered, he comes a little closer to that goal. [Daily Beast]

That seems a little overstated: Most wars fought under the banner of religion are really about terrestrial conquests — land, money, power (see Michael Brendan Dougherty's essay about Ireland) — and ISIS is probably no different. But Baghdadi needs men and money and weapons, and fighting "the Jews, the crusaders, their allies, and with them the rest of the nations and religions of kufr, all being led by America and Russia, and being mobilized by the Jews" — as the first issue of ISIS's glossy propaganda magazine explained — is a better recruitment call than "come help me get rich and set up a new country."

After the Sept. 11, 2001, attacks, President George W. Bush was careful to emphasize repeatedly that Islam is "a religion of peace." His subsequent attacks on majority-Muslim lands may have blunted that message, but the Bush White House saw the importance of not making the "war on terror" into a "holy war on terror." President Obama has made similar statements. It's obviously the right thing to do.

Pope Francis was not calling for a Christian crusade against ISIS — as Ed Morrissey at The Week and Elizabeth Stoker Bruenig at The Daily Beast cogently explain, the pope's impromptu remarks were a nuanced call for true international (meaning United Nations) action to protect all groups targeted by ISIS, including Iraq's embattled Christians, and well in line with Catholic "just war" teachings. But in this battle against ISIS, nuance tends to get lost in translation.

Baghdadi is almost certainly trying to provoke a U.S. military response (even as he reportedly fled back to Syria as soon as the U.S. bombs started falling), and it's vital that we ask why, especially as the U.S. seems to be on the verge of going all-in on the battle against Baghdadi's caliphate (well, least the part in Iraq).

But the U.S. has to be clear, to itself and the world, that this is about fighting brutal genocidal killers who slaughter and pillage Muslims as well as non-Muslims. This isn't America's war. And it isn't a holy war.